Amazon.com has blocked advertisements for a forthcoming book that questions the transgender “craze” among teenage girls.

Author Abigail Shrier, who also writes columns for the Wall Street Journal, revealed Saturday night that Regnery Publishing had been informed that ads for her book, Irreversible Damage: The Transgender Craze Seducing Our Daughters, had been blocked by Amazon under a policy that prohibits questioning gender identity.

The book, which Breitbart News has obtained, focuses on the struggles of mothers — many of them liberal, feminist, or even lesbian — who are suddenly faced with teenage daughters who no longer wish to identify as female.

Some of the girls undergo irreversible surgery — such as “top” surgery to remove their breasts — before they can change their minds.

Through extensive interviews and research, Shrier documents the spike in the number of girls who wish to identify as transgender. She suggests that some of the interest may be driven by popular culture, peer pressure, and the intervention of health professionals.

Fox News reported Saturday:

Amazon did not respond to repeated requests for comment. But in an email Regnery provided and said was sent by Amazon on Thursday, the online retailer said: “It contains elements that may not be appropriate for all audiences, which may include ad copy/book content that infers or claims to diagnose, treat, or question sexual orientation. Hence, this campaign will not be allowed to be advertised.”

Amazon’s effort to block advertising for a book that merely questions transgender identity raises questions about censorship, and whether such actions will produce a “chilling effect” on academic research and public debate.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News and the host of Breitbart News Sunday on Sirius XM Patriot on Sunday evenings from 7 p.m. to 10 p.m. ET (4 p.m. to 7 p.m. PT). His new book, RED NOVEMBER, is available for pre-order. He is a winner of the 2018 Robert Novak Journalism Alumni Fellowship. Follow him on Twitter at @joelpollak.